Modern cars are basically rolling computer networks. When you only use a basic...

https://www.mediafire.com/file/77eba7osq6tv0c5/pdf-93939-6247.pdf/file

Modern cars are basically rolling computer networks. When you only use a basic OBD reader, you are just reading the surface layer of a much deeper problem. You need professional diagnostic software to talk to every ECU and see the actual live data stream